salt bath annealing does not work

Experimental setup:
SBA with PID, set at 932*F
Salt Level just below the bottom of the holder, see first image.
3x S&B 6,5 Creedmoor brass
3x MEN 303 British brass
Tempilaq 450 strips, from 1" above case mouth, down to the head (I didn't want templac in the salts)(Yes, my paint lines kinda look like dicks)
I used a metronome app, set to 60 BPM, to time brass dunks. One each size at 6 seconds, one at 12, and (303only) one at 12 seconds dunk, with an immediate water quench. One piece of 6,5CM had the tempilaq ruined when i grabbed the strip with my glove pulling it out.
IMG_0707.jpg

IMG_0710.jpg

Results
IMG_0711.jpg

From left to right:
6,5CM 6 seconds, 6,5CM 12 seconds, 303 6 seconds, 303 12 seconds, 303 12 seconds with water quench.



EDIT: Those are 303 cases, not 8x57. I'm an idiot. Guess which akro bins are right next to each other...
 
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Experimental setup:
SBA with PID, set at 932*F
Salt Level just below the bottom of the holder, see first image.
3x S&B 6,5 Creedmoor brass
3x MEN 8x57 brass
Tempilaq 450 strips, from 1" above case mouth, down to the head (I didn't want templac in the salts)(Yes, my paint lines kinda look like dicks)
I used a metronome app, set to 60 BPM, to time brass dunks. One each size at 6 seconds, one at 12, and (8x57 only) one at 12 seconds dunk, with an immediate water quench. One piece of 6,5CM had the tempilaq ruined when i grabbed the strip with my glove pulling it out.
View attachment 7408188
View attachment 7408189
Results
View attachment 7408191
From left to right:
6,5CM 6 seconds, 6,5CM 12 seconds, 8x57 6 seconds, 8x57 12 seconds, 8x57 12 seconds with water quench.
Whelp, I’d say it looks like 12 seconds is safe for your case heads
 
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I've not yet started SBA (just ordered the salt and base) so I'm not familiar with the setup. Is that the normal depth of salt to plunge your brass into? I'd think you'd just stick the mouth into the salt, stopping at the start of the shoulder.

It’s about average, with the caveat I just topped up my salts the last time I annealed. You can go as low as you like as long as the thermoprobe is submerged appropriately for temp reading.
 
ken4570tc in WY, You keep going with your SBA. Truth be told, it's a more stable heat source than induction.
Not that the stability of the temperature or time matters at those low temps. Unless the brass is 100% recrystallized, there's no such thing as optimal hardness/softness because the cases are all over the shop in the interim stages. What is "THE OPTIMAL HARDNESS" anyway?
For a start, taking your temps to 500 C is actually taking the brass into the start of the recrystallization phase. You'll need more time than is practical at 500 C but, annealing is cumulative so, try your 12 second cycles 3 or 4 times after allowing the brass to cool in between cycles. Test your seating force & see if there's a noticeable softening.
The AMP takes the brass to 550C so, they definitely take the brass to the start of recrystallization but, 3 or 4 0r 10 seconds in no way guarantees the brass is the same hardness case to case. At 550C, depending on initial brass hardness, at best, 15 mins to 100% recrystallization. Your GUESS is as good as mine as to how much recrystallization takes place in 3 or 4 seconds. NVFM is my guess.
 
I've got my salt bath setup all built. I bought my salts from a chemical supplier, picked up an extra lead pot to dedicate to it, and built my own stainless steel top/shell holder. The shell holder part is adjustable for depth, and I have a digital thermocouple setup to monitor temps.

I also have all the pieces rounded up to make a very nice induction unit. I will continue work on it as time and inclination are available.

I will use salt bath for now, then when the induction unit is finished, determine which one I like. When I first read that article from the induction people that SBA doesn't work I was disheartened, but further study seems to point to it working just fine, (I guess.)

Vettepilot
 
When I get time, I have a fairly good test for my home built SBA setup. I had a defective sizing die bump the shoulders back .013" on about 50 30.06 cases. I'm going to anneal them with my SBA, then fire-form them. We'll see what happens...

Vettepilot
 
If it heats the brass to 500c or thereabouts, it will work pretty much the same.
The only reservations I have with SBA is that, unlike those that are taking the brass to 700f & stress relieving only in the time frames they use, SBA takes it to 930 F which, takes the brass to a critical temperature where recrystallization enters into an exponential time frame. Because annealing/recrystallization is cumulative, there is the definite possibility that you will soften the case head over successive cycles. Since brass cases are an excellent heat radiator & difficult to heat, the case head may not reach this critical temp but, because the cases are partially submerged , inside & out in a much greater mass, I believe this will tend to soak the cases more quickly than flame or induction. Over 6 or 8 seconds, you should be fine &, get a better result than those taking the brass to 700 or 750f but, you just have to be mindful.
This whole annealing thing was originally started by a couple of old guys who took some information from the cartridge manufacturers & thought it would be a good idea. Cartridge manufacturers anneal at specific temps for their own very specific purposes which, have little to do with the hand loader. We are not constrained by brass formability during case forming, high speed ammunition processes, packaging, handling & transportation & etc. Manufacturers require the finished product to be able to withstand some considerable abuse whilst maintaining original specification & function.
There were a whole lot of claims made early on which were entirely baseless & had little to no association with how or why the manufacturers were annealing. Although it is true that manufacturers do indeed "final anneal" at the completion of case forming, they, unlike us, do this to stop age cracking. I cannot find anything in any historical literature or, in any commissioned study which suggests otherwise.
I anneal differently but, that's another story.
 
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When I get time, I have a fairly good test for my home built SBA setup. I had a defective sizing die bump the shoulders back .013" on about 50 30.06 cases. I'm going to anneal them with my SBA, then fire-form them. We'll see what happens...

Vettepilot

Considering we blow shoulders forward on Dashers and 6BRA with medium loads, I'm sure nothing exciting will happen.
 
When I get time, I have a fairly good test for my home built SBA setup. I had a defective sizing die bump the shoulders back .013" on about 50 30.06 cases. I'm going to anneal them with my SBA, then fire-form them. We'll see what happens...

Vettepilot

.013 isn't much. New brass is normally sized under minimum SAAMI. Fired from a chamber on the big end of maximum it is pretty easy to see .020 of net growth.
 
Yeah, I'm not expecting problems with them. My plan goes like this. In order to "blow out" the neck and not stretch the case body, I am going to load up some 30-30 cast bullets I have long; out to light jam length. Loaded with maybe 10 to 12 grains of fast powder, this should fire form them back to my chamber spec. As mentioned, I will anneal them first. I need to use up these 30-30 cast bullets anyway...

Vettepilot
 
Yeah, I'm not expecting problems with them. My plan goes like this. In order to "blow out" the neck and not stretch the case body, I am going to load up some 30-30 cast bullets I have long; out to light jam length. Loaded with maybe 10 to 12 grains of fast powder, this should fire form them back to my chamber spec. As mentioned, I will anneal them first. I need to use up these 30-30 cast bullets anyway...

This is asking for misfires and squibs. -06 case capacity and 10gr of powder means a very low fill, which has the potential to 1) not light the powder and b) cause wonky pressure spikes. Also keep in mind, just lighting off a primer can have enough umph (technical term) to push the bullet out of the case.

I think most 06 reduced loads start at 20 or so grains of powder, but most will be listing trailboss or the like.

Look at the benchrest guys fireforming the small sixes - just run a moderate book load for the (base) caliber, no need to jam since or make a false shoulder or anything.
 
Yeah, I'm not expecting problems with them. My plan goes like this. In order to "blow out" the neck and not stretch the case body, I am going to load up some 30-30 cast bullets I have long; out to light jam length. Loaded with maybe 10 to 12 grains of fast powder, this should fire form them back to my chamber spec. As mentioned, I will anneal them first. I need to use up these 30-30 cast bullets anyway...

Vettepilot
Shooters World "Buffalo" powder can go as low as 10 grains safely for bullets from 125 to 180 grains in the 30-06 . This is published data on their site . Please note they called for jacketed bullets . Not sure how that translates for cast lead bullets . 1200 FPS was listed for one bullet .

 
Just as an FYI. Salt bath annealing is used in industry/manufacturing to anneal large brass components all the time, and has been since about the 1930s, and will be for a very long time.
I use it with what I feel to be impeccable results, especially for a newbie shooter. I chose it based on my experience in industry/manufacturing and it’s cost effective nature, and knowing that my goal isn’t to completely anneal the brass into its softest “dead” state, as it seams the AMP does, but to simply take the stress out of the most heavily worked area of the case. The neck and shoulder. My brass lasts forever. I had 15 firings on LRP Alpha 6.5CM before I retired it and moved to SRP in a new barrel. That batch has exactly 10 firings on it now as well and I haven’t lost a single case. My SD/ES are certainly acceptable to me, and the accuracy and precision of my rifle far exceeds anything I thought I could do personally.
If I felt like sacrificing a case, a could even throw it on the Brinell tester and get a reading before and after, but I feel that’s moot at this point.
Those that use SBA, don’t seem to have any issues with their brass at all. In fact, there’s more threads on the neck friction increase due to the surface texture left by induction annealing causing issues with SD/ESs than there is with people struggling with their SBA setups.
Truth is, SBA is unsurpassed as far as temperature control of the brass is concerned.
I've listed a study conducted by W.Y.Yeung, J.Hirsch & M.Hatherly of the "SCHOOL OF MATERIAL SCIENCE & ENGINEERING, UNIVERSITY OF NSW AUSTRALIA In conjunction with INSTITUTE FUR METALLKUNDE UND METALLPHYSIK, Aachen West Germany.
In this study, they used the SBA method in order to achieve the required results within the temperatures & timeframes necessary.
Annealing of 2mm thick 70/30 cartridge brass was carried out in SBA "The thickness of the specimen material was such that <1 sec was required to reach the bath temperature. Specimens were examined after annealing at 300C & 900C "
The title of the study is..."ROLLING & ANNEALING OF FINE GRAINED 70 : 30 BRASS"
The primary focus of this study was rolling textures & microstructures developed in fine grained (2-5 micron) cold worked brass. This is pretty heavy reading but, interesting nonetheless.
 
Experimental setup:
SBA with PID, set at 932*F
Salt Level just below the bottom of the holder, see first image.
3x S&B 6,5 Creedmoor brass
3x MEN 303 British brass
Tempilaq 450 strips, from 1" above case mouth, down to the head (I didn't want templac in the salts)(Yes, my paint lines kinda look like dicks)
I used a metronome app, set to 60 BPM, to time brass dunks. One each size at 6 seconds, one at 12, and (303only) one at 12 seconds dunk, with an immediate water quench. One piece of 6,5CM had the tempilaq ruined when i grabbed the strip with my glove pulling it out.
View attachment 7408188
View attachment 7408189
Results
View attachment 7408191
From left to right:
6,5CM 6 seconds, 6,5CM 12 seconds, 303 6 seconds, 303 12 seconds, 303 12 seconds with water quench.



EDIT: Those are 303 cases, not 8x57. I'm an idiot. Guess which akro bins are right next to each other...
You MUST be a fucking bullet sponge, Jar Head! Only a Marine could put Templaq on cases and it come out looking like dicks without even trying!
 
It would seem to me, from those pics of the 750f Tempilaq, that 6 to maybe 8 or 9 seconds would be the way to go. The 12 second samples seem to have gotten to 750f a bit low.

Oops. My bad. He was using 450f Tempilaq. I'd like to see the same test with 750f Tempilaq. Maybe 930 for 12 seconds IS the way to go...

Vettepilot
 
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